The invention relates to a blank intended for producing a shaped element in an absorbent product, such as a sanitary towel, an incontinence pad or panty liner, which blank is made from a rigid material and initially has a plane and essentially elongate shape with a longitudinal direction and a transverse direction, two short sides and two long sides, a central portion and two end portions.
The invention also relates to a shaped element for an absorbent product, such as a sanitary towel, an incontinence pad or panty liner, which shaped element is made from a rigid material and has an essentially elongate shape with a longitudinal direction and a transverse direction, two short sides and two long sides, a central portion and two end portions, one end portion of which has a bowl-shaped portion.
The invention also relates to an absorbent product, such as a sanitary towel, an incontinence pad or a panty liner, which product has an essentially elongate shape with two end portions and a central portion located between the end portions, and a longitudinal center line, which product comprises a shaped element and which product has a bowl-shaped portion in one end portion and a ridge-like raised portion in the other end portion.
The invention also includes a method of producing a shaped element according to the above, and also a method of producing an absorbent product, such as a sanitary towel, an incontinence pad or a panty liner.
Conventional absorbent products of the type referred to above usually have a plane shape. As the genital area of women does not have a correspondingly plane appearance, problems can therefore arise in fitting and wearing such products. The bearing of the product against the body is not the best that could be desired and if looseness occurs there is also a great risk of leakage.
In order to solve this problem, it has been proposed that the absorbent products should be of bowl-shaped design rather than plane. Broadly speaking, this shape fits better against the contours of the body. A bowl-shaped contour can be achieved by, for example, fitting elastic to the product. EP 155 515 describes how an absorbent product is imparted a bowl-shaped appearance by elastic being fitted in the longitudinal side edges of the product. WO 96/20679 describes an absorbent product which comprises a resilient component and tensioning members in order to give the product a bowl-shaped appearance.
A problem with products of the abovementioned type is that they do not fit particularly well against the anatomy of the wearer but simply have a generally bowl-shaped appearance. Such a shaped product therefore does not have a good fit against the body.
Furthermore, gaps tend to occur between the body of the wearer and the panties of the wearer because many women wear panties of inferior quality, either from the outset or as a result of great age, during their menstruation. When neither the absorbent product nor the panties are capable of maintaining good contact with the body of the wearer, the risk of leakage of menstrual fluid past both the absorbent product and the panties becomes great.
EP 302 523 describes an absorbent product which has a three-dimensionally designed, anatomically adapted shape. The product has an end portion of flat or concave design and an end portion which is provided with a raised portion. The flat or concave end portion is intended to be placed in front of the mons pubis of the wearer and the end portion comprising the raised portion is intended to fit against the buttocks of the wearer. The three-dimensional design of the product is obtained by folding a moderately rigid absorption body. In order to make the raised portion permanent, the rear side of the product is provided with a glued surface in the end portion that is to have the raised portion. When the raised portion has been created, it is preserved with the aid of the glue. One problem with a product of this type is that it tends to collapse under the pressure from the body of the wearer. Another problem is that the glued sealing of the raised portion loses its adhesion and the product is then flattened out.
In order to solve this problem, it has been proposed that products are provided with dimensionally stable, rigid members. Such products are described in SE-A-9604223-9 and SE-A-9604221-3. The members, or shaped elements, which bring about the dimensional stability are three-dimensionally designed members made from material which resists crumpling and flattening when it is subjected to forces from the body of the wearer, for example when the wearer walks or sits on the product.
A problem which is just as great as that constituted by plane absorbent products when they are to be adapted to the three-dimensional anatomy of the wearer is that constituted by the three-dimensional absorbent in the production process. Three-dimensional parts are difficult to handle in a production process, for example when they are to be joined together to form an absorbent product.
An object of the invention is to remedy the abovementioned problems and produce a shaped element for absorbent products which is easy to produce and also an absorbent product comprising the shaped element, which product is leakproof, comfortable and easy to produce.
A blank of the type referred to in the introduction, in which problems associated with previously known such products have essentially been removed, is according to the invention characterized in that one end portion on the blank is wider than the central portion and has a width which increases towards the short side of the blank and the other end portion has an elongate cutout, or slit.
According to an embodiment of the invention, the widest part on the end portion is 1.5-5 times as wide as the narrowest width on the central portion.
According to another embodiment, the shaped element has been joined together to form a raised portion in one end portion, from a plane blank, and the bowl-shaped portion has been created with the aid of a fold indication extending in the transverse direction of the shaped element. Additional fold indications, can be arranged essentially in the longitudinal direction of the blank, in at least the central portion of the blank, on each side of a longitudinal center line through the blank.
The invention also includes an absorbent product which is characterized in that a ridge-like raised portion in one end portion of the product has been created by the shaped element being joined together to form a raised portion from a plane blank, and in that a bowl-shaped portion has been created with the aid of a fold indication extending in the transverse direction of the shaped element.
According to an alternative embodiment, the absorbent product has leakage barriers arranged on both sides of the longitudinal center line.
The invention also includes a method of producing a shaped element, which is characterized in that a blank intended to constitute the shaped element is produced in plane form with an essentially elongate shape with a longitudinal direction and a transverse direction, two short sides and two long sides, two end portions and a central portion, where one end portion is given a width which increases towards the short side of the blank and the other end portion is provided with a cutout, the blank is folded double along a longitudinal center line of the blank so that two surfaces are formed on the blank, the cutout is joined together and the joined parts are folded up into a three-dimensional state.
According to the invention, the fold indications can be arranged in the longitudinal direction of the blank before the cutout is joined together.
The invention also includes a method of producing an absorbent product, according to which a blank intended to constitute a shaped element in the absorbent product is produced in plane form with an essentially elongate shape with a longitudinal direction and a transverse direction, two short sides and two long sides, two end portions and a central portion, where one end portion is given a width which increases towards the short side of the blank and the other end portion is provided with a cutout, the blank is folded double along a longitudinal center line of the blank so that two surfaces are formed on the blank, an absorption layer and then an outer layer are arranged on each surface, after which the side edges along the cutout formed, the absorption layers and also the outer layers are joined and the joined parts are folded out into a plane state.
According to an alternative embodiment of the method of producing the absorbent product, two fold indications are arranged essentially in the longitudinal direction of the blank, in at least the central portion of the blank, one on each side of the longitudinal center line.
The abovementioned problems are solved by the present invention. This is brought about by a blank for a shaped element being produced from a plane piece of rigid material. The blank is clipped, punched or cut out from the piece of material so that it has an essentially elongate shape with two long sides and two short sides, two end portions and a central portion. One end portion has a width which is considerably greater than the width at the narrowest part of the blank, which is the central portion. The other end portion has a longitudinal slit or cutout in the longitudinal direction of the blank. The cutout is arranged along a longitudinal center line extending through the blank. The longitudinal center line is in this connection an imaginary line which divides the blank into two preferably symmetrical parts of the same size. The center line is arranged in the longitudinal direction of the blank at the same distance from its two long sides. The slit or cutout is arranged in such a manner that, in the part where the cutout is arranged, the blank assumes a shape with two elongate parts which diverge in relation to the longitudinal center line.
The intention of arranging a shaped element in an absorbent product is to be able to impart to the product a three-dimensional shape which is retained and possibly also accentuated during use of the product. Materials suitable for producing the blank for the shaped element must have adequate bending and torsional rigidity in order to resist deformation during use. Polyethylene or polypropylene laminates with a layer thickness of at least 0.4 mm can be mentioned as examples of plastic materials which have been found to have adequate bending rigidity and torsional rigidity to achieve the necessary dimensional stability. The material rigidity of a plastic film which is suitable for use as a shaped element in a product according to the invention should exceed 100 N, measured according to ASTM D 4032-82 xe2x80x9cCircular Bend Procedurexe2x80x9d, which method is described in detail in EP 336 578. In this connection, material rigidity means the bending rigidity of a plane material layer.
After the blank has been cut out, it is folded double along the longitudinal center line and along the cutout. In this state, the cutout is joined together. This is done by, for example, welding or gluing. The shaped element has thus been formed. That is to say, when the blank has been cut out and joined together so that it needs only to be folded up in order for it to assume a three-dimensional shape, it is referred to as a shaped element.
In this plane state, the shaped element can be packed and supplied to the user who can then herself make an absorbent product by providing the shaped element with absorption layers and if appropriate outer layers. In this way, a reusable shaped element can be produced, something which is economically advantageous. The user can replace absorption layers and outer layers but use the shaped element a number of times.
Many users, however, attach great importance to convenience and prefer to buy ready-made absorbent products. After the blank has been joined together along the cutout to form a finished shaped element, the shaped element is provided, while still in a folded plane state, with an absorption layer and an outer layer on each side. The absorption layer and the outer layer are joined together by means of, for example, welding or gluing. Alternatively, outer and absorption layers are arranged on the blank before the cutout is joined together and the cutout, the absorption layers and the outer layers are joined in one and the same step. A further alternative for joining the absorbent product together is that the blank is folded and the cutout is joined together so that the shaped element is prepared. Then a continuous absorption layer is folded around the shaped element while it is still folded together, after which a continuous outer layer is folded in the same way around the folded-together shaped element. In this way, a complete absorbent product is obtained without the outer and absorption layers having to be joined together from two parts each.
In conventional products, a liquid-impermeable layer is joined to the rear side of the absorption layer and the product, which is that side of the product which is intended to face towards the undergarments of the wearer during use, that is to say away from the wearer. This is so as to protect the undergarments of the wearer against any leakage of fluid through the whole product. With an absorbent product according to the invention, no such extra liquid-impermeable layer is necessary. As the shaped element is usually made of liquid-impermeable material, the shaped element constitutes the liquid-impermeable rear side. A product according to the invention is thus simpler in this way also than conventionally constructed absorbent products.
The entire production of the absorbent product has been carried out in plane form and the production process for a dimensionally stable, three-dimensional product has thus been simplified considerably in relation to production processes in which a shaped element is moulded, as in, for example, SE,A, 9604224-7.
When an absorbent product according to the invention, comprising a shaped element according to the invention, is folded up into its use state, it will fit well against the anatomy of the wearer. The end portions and the central portion on the blank or shaped element do not constitute three delimiting parts of the same size of the blank or shaped element but are indicated in order to describe the three different appearances the blank has in the longitudinal direction. One end portion, the front end portion, is intended to face forwards on the user when used in a sanitary towel. Forwards on the wearer means that the short side of the end portion will be that part of the towel which faces towards the abdomen of the wearer. The front end portion has a bowl-shaped portion. When a sanitary towel comprising a shaped element according to the invention is positioned with the bowl-shaped end portion forwards on the wearer, said portion will surround the mons pubis of the wearer. The other end portion, the rear end portion, is intended to face backwards on the wearer during use. Backwards on the wearer means that the short side of the end portion will be that part of the towel which faces towards the back of the wearer. The rear end portion has a ridge-like raised portion. When a sanitary towel comprising the shaped element according to the invention is positioned with the ridge-like end portion backwards on the wearer, that is to say towards the bottom region of the wearer, the product will naturally fit against the anatomy of the wearer and will therefore also bear closely against the body by itself.
The central portion on the shaped element has a raised portion. When a sanitary towel comprising a shaped element according to the invention is positioned against the body of the wearer, the raised portion on the central portion will fit against the vestibule of the wearer. The raised portions in the central portion and the end portion can constitute a continuous raised portion. The central portion and the rear end portion have been folded up so that they have ridge-like raised portions on the upper side of the shaped element. A fold indication can be arranged on the front end portion in order to facilitate the end portion being folded up and turned inside out so that the end portion assumes a bowl-shape on the upper side. Such a fold indication can consist of perforations or of a material weakening produced by, for example, cold or hot stamping. On turning inside out, the bowl-shaped portion is folded up towards the upper side on the shaped element so that the portion forms an angle with the other parts of the shaped element, seen from one long side of the shaped element. The angling and the bowl-shape together result in the shaped element fitting well against the mons pubis of a prospective wearer. The upper side on the shaped element is in this respect the side which is intended to face towards the wearer during use. The rear side on the shaped element is the side which is intended to face away from the wearer during use. In a corresponding manner to a complete absorbent product, the front end portion on the shaped element is the end portion which is intended to face forwards on the wearer during use, that is to say the end portion which is intended to face towards the abdomen of the wearer. The rear end portion on the shaped element is then the end portion which is intended to face backwards on the wearer during use, that is to say the end portion which is intended to face towards the back of the wearer.
In order further to improve an absorbent product according to the invention, comprising a shaped element according to the invention, the shaped element can be provided with one or more longitudinal fold indications. These fold indications contribute to shaping the shaped element and thus the absorbent product according to the anatomy of the wearer. Another purpose of the fold indications is to create channels in the shaped element and thus leakage barriers in the finished product. As the shaped element and the finished product have ridge-like raised portions in the central portion and one end portion, there is a risk of fluid running down the inclined side surfaces of the raised portions and on out past the side edges of the product, leading to side leakage. Leakage barriers moulded in a dimensionally stable shell for an absorbent product having ridge-like raised portions are described in SE,A, 9702398-0. Such leakage barriers mean, however, that the shaped element has a three-dimensional shape throughout the entire production process of the absorbent product.
According to the present invention, the fold indications are arranged in the shaped element before it is joined together with the outer layer and the absorption layer to form the absorbent product. It is also possible to arrange the fold indications after joining together. In this way, the shaped element has a plane shape throughout, broadly speaking, the entire production process of the absorbent product. Fold indications can be produced in a number of different ways. For example, the fold indications can consist of stampings or weakenings in the material, such as grooves or the like produced by means of small wheels or rollers. Alternatively, the fold indications can be produced by compression moulding. It is also possible to fold the finished product in the desired manner and make the folds permanent by heating or pressing.
Fold indications which serve as side leakage barriers on each side of the ridge-like raised portions in the central portion and the end portion are advantageously arranged in the longitudinal direction of the shaped element, starting from the longitudinal center line where it intersects a transverse fold line made in the front end portion in order to create the bowl-shape in this portion. From this starting point, a fold line is arranged on each side of the longitudinal center line and on both sides of the raised portions in the central portion and the end portion. The fold lines consist of straight lines which diverge from the center line so that channels are formed in the shaped element on the central portion and relatively large parts of the end portion. The fold lines stop a few centimetres from the short side of the product in the end portion which has the raised portion.
The fold lines do not have to be straight but can, for example, bend away towards the long sides of the shaped element. This results in a product with a further improved body shape. Another way of obtaining leakage barriers and increased adaptation of the absorbent product to the body is to arrange a number of fold lines on each side of the longitudinal center line and on both sides of the raised portions in the central portion and the end portion. For example, two or three fold lines can be arranged on each side of the center line. Extra lines, in addition to one on each side of the longitudinal center line, can start from the same point as the two first fold lines. That is to say from an imaginary intersection point between the longitudinal center line and the transverse fold line which makes the bowl-shape of the end portion possible. From this starting point, they diverge further from the longitudinal center line. Additional lines can also be arranged parallel to the two original fold lines. All the fold lines described are arranged at a distance of at least several millimetres from the long sides of the shaped element in order to create channels and consequently leakage barriers in the finished absorbent product.
In order to obtain better adaptation of the absorbent product to the body, additional fold lines can be arranged on the shaped element. For example, arc-shaped fold lines, which are concave towards the longitudinal center line, can be arranged on each side of the longitudinal center line in the end portion which has the raised portion. That is to say arc-shaped fold lines are arranged around the raised portion. Such fold lines can of course also be arranged in the central portion or otherwise common lines running through both the central portion and the end portion can be arranged.
In order to obtain a further improved adaptation to the body of the end portion against the mons pubis of the wearer, that end portion of the product which is to form the bowl-shaped portion in the shaped element can also be cut out with a cutout. In this way, greater rounding of the bowl can be obtained. The production process is of course more complicated because two cutouts are to be joined together before the shaped element can be folded up into its final shape.
The invention also includes an absorbent product which comprises the shaped element according to the invention. The designations used for the product and for the shaped element apply similarly for the absorbent product also. For example, the front end portion on the blank is intended to constitute the front end portion on the shaped element which is arranged in the front end portion on the absorbent product.
An absorbent product comprising a shaped element according to the invention does not require any fastening arrangement such as glued surfaces on the rear side of the product. A product according to the invention stays in place naturally by means of its anatomical design. Such products are described in SE,A, 9604222-1 and SE,A,9604224-7. The decisive factor with regard to whether the product stays in place by itself is the rigidity of the shaped element and the design of the shaped element. The end portion which is intended to face forwards on the wearer during use is to be wider than the central portion. It is also an advantage if the other end portion is somewhat wider than the central portion but this is not crucial for fastening. Preferably, the widest part on the front end portion is 1.5-5 times as wide as the smallest width on the central portion.
In order that the shaped element and thus the product will not cause discomfort for the wearer and possibly leakage, it is important that the cross section or width of the central portion is adapted according to the anatomy of the wearer. The most critical area in the crotch region of the wearer from the point of view of comfort as far as the width of the product is concerned is where the muscle group passes which has its origin on the inside of the pelvic diaphragm and its attachment along the thigh. This muscle group consists of the adductor brevis, adductor longus, gracilis and adductor magnus muscles.
Measurements have shown that the distance in the crotch region of the wearer between the adductor muscle groups on the left side and the right side is surprisingly alike for all people and is around 30 mm. Fatness of course influences the width between the thighs but the width between the muscle groups in the crotch region is the same and it is this width which determines whether a product may feel as if it rubs. The fat tissue settles on the outside of the muscles but does not contribute to any feeling of discomfort. If the product is constructed from a very rigid material, the width of the central portion should therefore not exceed 35 mm, at least in the area which is to fit between the muscle groups. This critical area is approximately 5-15 mm long in the longitudinal direction of the product.
A product according to the invention, which stays in place without any special fastening arrangements, comprises a shaped element made of a rigid material, which shaped element comprises a front end portion which is 1.5-5 times as wide in its widest portion as its central portion is in its narrowest portion. The rear end portion is advantageously also wider than the central portion so as to avoid the absorbent product xe2x80x9cwanderingxe2x80x9d in any direction.
The central portion on the shaped element is 35 mm or narrower, within at least an area of the central portion which is 5-15 mm long. The front end portion is wider on that part of the end portion which faces towards the front short side of the product, that is to say the side which is intended to face forwards on the wearer during use, than on the part which faces towards the central portion. The front end portion can have, for example, a triangular shape. The front end portion is 52.5-175 mm wide at its widest. The front end portion is advantageously also shaped so that it has an angle in relation to the other parts of the shaped element, seen from one long side of the shaped element.